Immunotherapy against several tumors of the blood, such as acute myeloid leukemia (AML)

Abstract

The present invention relates to peptides, nucleic acids and cells for use in immunotherapeutic methods. In particular, the present invention relates to the immunotherapy of cancer. The present invention furthermore relates to tumor-associated cytotoxic T cell (CTL) peptide epitopes, alone or in combination with other tumor-associated peptides that serve as active pharmaceutical ingredients of vaccine compositions that stimulate anti-tumor immune responses. The present invention relates to several novel peptide sequences and their variants derived from HLA class I and HLA class II molecules of human tumor cells that can be used in vaccine compositions for eliciting anti-tumor immune responses.

The invention claimed is: 
     
       1. A modified peptide consisting of the amino acid sequence of KLQEQLAQL (SEQ ID NO: 266), wherein a non-peptide bond replaces a peptide bond. 
     
     
       2. A fusion protein, comprising
 (a) a peptide consisting of the amino acid sequence of KLQEQLAQL (SEQ ID NO: 266); and 
 (b) N-terminal amino acids 1-80 of HLA-DR antigen-associated invariant chain (Ii). 
 
     
     
       3. A pharmaceutical composition comprising
 the peptide according to  claim 1 , or 
 a fusion protein comprising a peptide consisting of the amino acid sequence of KLQEQLAQL (SEQ ID NO: 266); and N-terminal amino acids 1-80 of HLA-DR antigen-associated invariant chain (Ii), and 
 a pharmaceutically acceptable carrier. 
 
     
     
       4. The peptide of  claim 1 , wherein said peptide is produced by solid phase peptide synthesis using a solid-phase support followed by removal from the solid-phase support by a composition comprising 95% trifluoroacetic acid and a 50% scavenger mix. 
     
     
       5. The peptide of  claim 4 , wherein the scavenger mix comprises ethanediol, phenol, and/or anisol. 
     
     
       6. The peptide of  claim 4 , further comprising removing the excess trifluoroacetic acid by evaporation. 
     
     
       7. The peptide of  claim 6 , further comprising purifying the peptide using a method selected from the group consisting of re-crystallization, size exclusion chromatography, ion-exchange chromatography, hydrophobic interaction chromatography, and reverse-phase high performance liquid chromatography. 
     
     
       8. The peptide of  claim 7 , wherein the purification is performed using ion-exchange chromatography using an organic or inorganic acid. 
     
     
       9. The peptide of  claim 8 , wherein the organic acid is selected from the group consisting of acetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid, malic acid, malonic acid, succinic acid, maleic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, methane sulfonic acid, ethane sulfonic acid, p-toluenesulfonic acid, and salicylic acid, and the inorganic acid is selected from the group consisting of hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid phosphoric acid. 
     
     
       10. The peptide of  claim 9 , wherein the acid is acetic acid or hydrochloric acid. 
     
     
       11. The peptide of  claim 7 , wherein the purification is performed using ion-exchange chromatography using a base. 
     
     
       12. The peptide of  claim 11 , wherein the base is selected from the group consisting of sodium hydroxide, potassium hydroxide, ammonium hydroxide, calcium hydroxide, and trimethylamine. 
     
     
       13. The pharmaceutical composition of  claim 3 , wherein the pharmaceutically acceptable carrier is selected from the group consisting of saline, Ringer's solution, and dextrose solution. 
     
     
       14. The pharmaceutical composition of  claim 13 , further comprising additional pharmaceutically acceptable excipients and/or stabilizers. 
     
     
       15. The pharmaceutical composition of  claim 14 , wherein the additional pharmaceutically acceptable excipients are selected from the group consisting of buffers, binding agents, diluents, flavors, and lubricants. 
     
     
       16. A pharmaceutical composition comprising the peptide of  claim 1  and a pharmaceutically acceptable carrier and, optionally, pharmaceutically acceptable excipients, and/or stabilizers. 
     
     
       17. The modified peptide of  claim 1 , wherein the non-peptide bond is selected from the group consisting of —CH 2 —NH—, —CH 2 S, —CH 2 CH 2 —, —CH═CH—, —COCH 2 —, —CH(OH)CH 2 —, and —CH 2 SO—.